Do you think an 18 year old student has any hope of getting work as a freelance illustrator, just starting out in the industry. I've been drawing since i was a young child an have developed my skills for years but will anyone really want to buy my work, or am i aiming too high?
"If you are good enough, you are old enough."
I don't think you are aiming too high. Though I would suggest you look at alternative ways of getting commissions in the current climate, especially as the industry is very subjective in regards to art/design/illustration.
Have you looked at website like Etsy.com or Folksy.com where you can set up a shop quickly and easily, and appeal to like minded people? Build up a portfolio, and test the water as to how marketable your work is.
There is no such thing as aiming too high if the work you are producing is of suitable quality for your market. However, without an agent (which you probably can't obtain until you have a small body of published work to show them) you are going to have to know someone which means some serious networking.
I would try local publications and magazines to see if they will take anything from you, perhaps even waiving payment for now. Freelancing is all about reputation for supplying good quality quickly and with little fuss. If just one editor with the right contacts sees you can do that...
I don't think you are aiming too high but I know of a couple of excellent illustrators, with agents, who say that they are struggling in the current climate. I'm not sure that helps, but I don't think you should give up the idea if it's what you really want to do. Good luck